Given the prevalence of comorbid alcohol, drug, and psychiatric disorders, the accurate diagnosis of these conditions is vital for research. However, most fully- and semi-structured diagnostic procedures have not been designed specifically to address this problem. The Psychiatric Research Interview for Substance and Mental Disorders-Short Version (PRISM-S) is a clinician-administered diagnostic interview designed to yield DSM-IV primary and substance-induced diagnoses in heavy drinkers and drug users. The PRISM-S interview is complete, but software and training materials need to be developed before it can be distributed for general use. Work proposed for Phase I includes (1) development of data entry, data cleaning and diagnostic software; (2) development of training materials; and (3) piloting. Phase II will involve psychometric testing of the PRISM-S, including (1) a test-retest reliability study in alcohol, drug, and psychiatric subjects, balanced by gender and minority status; and (2) validity testing. This work would constitute further innovations of procedures that are departures from older methods. Developing a complete package of diagnostic materials for the PRISM-S would increase the commercial applications of the PRISM-S by appealing to a wider range of researchers, as well as clinicians and others interested in diagnostic training. PROPOSED COMMERCIAL APPLICATION: The PRISM will be useful for a very wide range of research studies requiring highly reliable diagnoses of DSM-IV alcohol, drug and psychiatric disorders. The scale will have the greatest commercial potential in academic/medical research settings and for pharmaceutical companies conducting drug trials in substance-using subjects. The PRISM-S may also have commercial applications in treatment settings that may wish to use the interview as part of their intake procedures.